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GCN Circulars

GCN Circulars are rapid bulletins submitted by and distributed to the community. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36219 results found.

  1. GRB 060108: Refined analysis of the Swift-BAT burst
  2. GRB 060108: Swift XRT position
  3. GRB060108: Swift detection of its 100th GRB
  4. GRB 060105: pseudo-z from spectral parameters of the prompt emission
  5. GRB 060105: Radio observations
  6. GRB 060105: MDM Observation
  7. Konus-Wind observation of GRB 060105
  8. GRB 060105: ISAS observations and near IR upper limit
  9. GRB 060105: Swift/UVOT upper limits
  10. GRB 060105: Mitsume optical observations
  11. GRB 060105: BAT refined analysis
  12. GRB 060102 - no XRT afterglow
  13. GRB 060105: XRT refined analysis
  14. GRB060105: Suzaku-XIS and -HXD observation plan
  15. GRB060105, optical observation
  16. GRB060105 : Kiso optical observation
  17. GRB060105: Swift detection of a bright long burst
  18. Swift-BAT trigger 175653 is not an astrophysical source
  19. GRB 060102: MDM Observation
  20. Swift-BAT trigger 175653 is probably not a GRB
  21. GRB 060102: Swift-BAT refined analysis
  22. Time Correction to GRB 060102
  23. GRB 060102: Swift-BAT detection of a burst
  24. GRB051211B: optical observations
  25. GRB051227: SARA Observations
  26. GRB 051221B: Optical Observations with Kuiper 1.54m
  27. GRB 051227: Likely host galaxy underlying afterglow position
  28. GRB 051227: optical observation
  29. GRB 051221A: VLA Radio Observations
  30. GRB 051227: Confirmed fading from Gemini observations
  31. GRB051227: further analysis of VLT images
  32. GRB 051227: optical afterglow
  33. GRB 051227: Swift/UVOT Upper Limits (Possible U-band
  34. GRB 051227: Gemini observations
  35. GRB 051227: Keck Spectroscopy
  36. GRB 051227: Magellan r'-band Imaging/Astrometry
  37. GRB 051227: refined analysis of VLT images
  38. GRB 051227: P60 Observations
  39. GRB 051227: MDM Observation
  40. GRB 051227: R-band object in the XRT error circle
  41. GRB 051227: Joint Swift-HETE Spectral Analysis
  42. GRB 051227: XRT refined analysis
  43. GRB 051227: Further analysis of the Swift-BAT burst
  44. GRB 051227: Refined analysis of the Swift-BAT burst
  45. GRB051227: SDSS pre-burst observations
  46. GRB 051227, optical observation
  47. GRB 051227: Swift detection of a burst
  48. IBAS_alert n. 2719 : not a real GRB
  49. Konus-Wind observation of GRB 051221A
  50. GRB051221A: Suzaku WAM observation of the prompt emission
  51. GRB 051221A: MDM Optical Observations
  52. GRB051016: analysis of the XMM-Newton observation
  53. GRB 051221A: Detection at 251nm with Swift UVOT
  54. GRB 051221A: Chandra Afterglow Position
  55. GRB 051221A: Refined spectral and temporal analysis of the Swift-BAT short hard burst
  56. GRB 051221B: ROTSE-III Optical Limits
  57. GRB 051221B: TAROT optical limits
  58. GRB 051221A: WSRT Radio Observations
  59. GRB 051221: Redshift from Gemini
  60. GRB 051221: Continued fading of optical afterglow
  61. GRB 051221B: Refined analysis of the Swift-BAT burst
  62. Possible GRB 051221B: MDM Optical Detection
  63. GRB 051221A: RAPTOR Fading Counterpart Constraint
  64. GRB 051221B: BOOTES optical observations.
  65. Possible GRB 051221B: Swift XRT position
  66. GRB 051211A: Evidence This Is a Short Burst from Analysis of Spectral
  67. Swift-BAT detection of a possible burst
  68. GRB 051221: Discovery of fading optical afterglow
  69. GRB 051221: Swift XRT refined analysis
  70. GRB 051221: Swift/UVOT upper limits
  71. GRB 051221: Possible nearby cluster
  72. GRB 051221: No variability in Gemini data
  73. GRB 051221: Correction to GCN #4368
  74. GRB 051221: Gemini observations
  75. GRB 051221: Improved astrometry of the IR counterpart
  76. GRB051221: K-band source
  77. GRB 051221: XRT position
  78. GRB 051221: Refined analysis of the Swift-BAT short hard burst
  79. GRB 051221: IR Observations at GRB+1hr
  80. GRB 051221: Swift detection of a bright short burst
  81. Swift-BAT discovery of hard x-ray transient SWIFT J1626.6-5156
  82. Refined analysis of the Swift-BAT detection of the RS CVn star II Peg
  83. GRB 051211B: optical afterglow
  84. Swift detection of an RS CVn flare star
  85. GRB051211A: possible optical candidate
  86. Swift Trigger 172767 is not a GRB
  87. GRB 051215: near-infrared observations
  88. GRB051215 - SDSS pre-burst observations
  89. GRB 051215: Swift detection of a possible burst
  90. GRB 051215: A short GRB in a cluster?
  91. GRB051105: optical observations
  92. GRB 051213: Swift-BAT refined analysis
  93. GRB 051211B, optical observation
  94. GRB 051213: Swift-BAT detection of a burst
  95. GRB 051211a: RTT150 optical observations
  96. GRB051211B, RBO optical observations
  97. GRB 051211A: Swift/UVOT upper limits
  98. GRB 051211B: Swift/UVOT upper limits - correction
  99. GRB 051211B: Swift/UVOT upper limits
  100. GRB 051211A,optical observation

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